DENV inhibits type I IFN production in infected cells by cleaving human STING

PLoS Pathog. 2012;8(10):e1002934. doi: 10.1371/journal.ppat.1002934. Epub 2012 Oct 4.

Abstract

Dengue virus (DENV) is a pathogen with a high impact on human health. It replicates in a wide range of cells involved in the immune response. To efficiently infect humans, DENV must evade or inhibit fundamental elements of the innate immune system, namely the type I interferon response. DENV circumvents the host immune response by expressing proteins that antagonize the cellular innate immunity. We have recently documented the inhibition of type I IFN production by the proteolytic activity of DENV NS2B3 protease complex in human monocyte derived dendritic cells (MDDCs). In the present report we identify the human adaptor molecule STING as a target of the NS2B3 protease complex. We characterize the mechanism of inhibition of type I IFN production in primary human MDDCs by this viral factor. Using different human and mouse primary cells lacking STING, we show enhanced DENV replication. Conversely, mutated versions of STING that cannot be cleaved by the DENV NS2B3 protease induced higher levels of type I IFN after infection with DENV. Additionally, we show that DENV NS2B3 is not able to degrade the mouse version of STING, a phenomenon that severely restricts the replication of DENV in mouse cells, suggesting that STING plays a key role in the inhibition of DENV infection and spread in mice.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aedes
  • Animals
  • Cells, Cultured
  • Chlorocebus aethiops
  • Cricetinae
  • Dendritic Cells / metabolism*
  • Dendritic Cells / virology
  • Dengue Virus / immunology*
  • Dengue Virus / metabolism
  • Dengue Virus / pathogenicity*
  • HEK293 Cells
  • Humans
  • Immune Evasion
  • Interferon Type I / biosynthesis*
  • Macrophages / metabolism
  • Macrophages / virology
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • RNA Interference
  • RNA, Small Interfering
  • Signal Transduction
  • Vero Cells
  • Viral Nonstructural Proteins / metabolism*
  • Virus Replication

Substances

  • Interferon Type I
  • Membrane Proteins
  • NS2B protein, flavivirus
  • RNA, Small Interfering
  • STING1 protein, human
  • Viral Nonstructural Proteins